What is the valency of carbon?

The valency of carbon is 4, which corresponds to its ability to form four covalent bonds with other atoms. This property arises from carbon's electronic configuration, with four electrons in its outermost shell (2s² 2p²). To achieve a stable electronic arrangement, carbon can share these four electrons with other atoms, allowing it to bond with various elements, including hydrogen, oxygen, nitrogen, and itself.

With a valency of 4, carbon is able to form a wide variety of compounds, including hydrocarbons and complex organic molecules, which are essential for life. This tetravalency is a key reason why carbon is often referred to as the backbone of organic chemistry, enabling the formation of diverse structures, from simple molecules like methane (CH₄) to large, intricate biomolecules like DNA and proteins.

Other options do not align with the actual bonding capabilities of carbon. For example, a valency of 2 would suggest carbon can only form two bonds, which does not reflect its versatility. Similarly, a valency of 3 or 1 would also limit the types of chemical structures carbon can participate in, making 4 the only valid answer.